We have prophets to help mankind to know the word of God. God spoke to us through His prophet Joseph Smith. He also spoke through Moses and Abraham.
Your religion attempts to resurrect what it thinks was the OT system, conveniently (but I have to conclude purposefully) forgetting that He Who was to come has indeed done so, making prophecy to discern the word of God at best seeing through a glass darkly. Thus Moses and Abraham saw. (NB: when Moses saw the almighty God, he could not look at Him directly)
Now, in the post-incarnational world transformed by Christ, the Word is revealed in the Person of Jesus Christ, our Lord, God, and Savior, Who has come and saved us by His holy sacrifice upon the life-giving cross.
So we must wonder at this strange religion which claims to be a form of Christianity -- and not only a form, but the only true from -- and yet operates in a fashion that implicitly denies the reality of the incarnation, which has transformed the world in which we all live. Christ's glorious incarnation and birth literally split
time itself into two (BC/AD), and yet it seems your religion prefers to pretend as though it remains in the pre-incarnational world.
Why is that? Why won't you join the rest of us in the years of our Lord (Anno Domini), not just on the calendar (as I assume you already do), but in your theology and the faith that is affirmed by it? You won't do it. Instead you cling to something else that you call the true faith that was 'lost' or 'taken from the world' or some such, but is in reality the musings of Joseph Smith and those who followed him, who were and are false prophets, one and all.
You do not have the faith of Abraham, Isaac, and Jacob. You have
not received the Savior, the God-man Jesus Christ. One with His Father and the Holy Spirit in the perfect, eternally united, uncreated and indivisible Holy Trinity (our God, as Christians). To present things otherwise is to pretend that Mormonism has the faith of Christians, which is the true faith in the reality of Christ's coming, incarnate by the power of the Holy Spirit (Who is
God, the Giver of Life...not an untrustworthy feeling/burning in the bossom) and of the Virgin Mary, for us men (humankind) and our salvation, and so on. (I don't feel the need to recite the Creed, as it is obvious to anyone with ears to hear and eyes to see how Mormonism falls short of the very basics of Christianity.)
Can you say the same? No. You refuse in favor of your bizarre system of 'prophets' who are not that, baptisms which are not that, 'the sacrament' which is not that (and 'sacrament meetings' in place of liturgy/mass...yes, I know you guys have your temple rituals which are scripted, but for one you won't talk about them, so we can't contrast and compare, and for another thing I've seen them, and they're nothing like a Christian liturgy of any type -- Orthodox, Catholic, High Church Mainline Protestant, etc.; it's freemasonry with some fables sprinkled through, in what looks to be bakers' clothing), and all this other nonsense.
So quit it with this "God talked to Abraham, and also Joseph Smith" type of reasoning. God did lots of stuff that we weren't commanded to continue, particularly in the OT since that's the covenant He made with Jews, and Christianity and Judaism are not the same religion (precisely because of Christ's coming, and their denial of Him). Have you seen any Christians slaughter any Amorites or whoever lately because God said to do so in the OT? Of course not. And so neither do we revert to the old ways beyond what the Church has accepted from Judaism prior to our being thrown from the temple (quite a lot; ask anyone who studies the history of the development of Christian liturgy, or read anyone who has written on the same, like Jaroslav Pelikan, Robert Taft, etc.), which was handled by the apostles themselves in council at Jerusalem circa AD 50, as recorded in the Bible itself (in the book of Acts).
So even if it your system were somehow a 'restoration' of anything ancient, which it absolutely is not, it would only mean that you are today 1,969 years behind the Church and the actual apostles who lived, learned from, and taught the pure faith from the lips of our Lord Himself, Whom they walked the earth alongside.
Your Joseph Smith or any of your other claimed prophets can say nothing of the kind beyond a few different versions of some supposed 'vision' that happened to Smith. That's rather odd, don't you think? Our Lord went through great pains after His resurrection to illustrate that He was
not a vision to the doubting disciple St. Thomas, telling him to put his hands into the wounds on our Lord's side. St. Thomas did so, and brought his experience with the risen Christ to India in AD 52. Within a few decades of Christ's mission on earth. And so all the apostolic churches were founded, not on some obscurantist 'vision' given to one man a la Joseph Smith or his spiritual forefather the imentally-unstable Muhammad, founder of Islam, but on the experience of the risen Christ.
Come to the living, incarnate, risen Christ in the Christian faith, and leave the strange superstitions and outmoded OT role-playing/play acting of Joseph Smith et al. behind. Only Christ saves. Joseph Smith and the Mormon religion's temple ordinances or whatever do not.